Radio frequency identification (RFID) is known in the field of automatic data capture. A transponder, known generally as a tag, is typically attached to an object and communicates wirelessly with an RFID reader or interrogator. RFID technology is used in a variety of applications including retail, industrial, transportation, tracking, security, animal and individual identification, etc. Transfer of data via RFID technology may be used, for example, for indicating the presence of the object, such as in electronic article surveillance (EAS), for obtaining data associated with the object, or for identifying the object. In an automatic identification system, the tag is typically programmed, either in advance during manufacture, or in the field by a user, with unique information, such as tag data including an identifying serial number, a stock number, a lot or batch number, a production date, time and temperature history, or other specific information related to the object.
The RFID reader typically includes a radio frequency (RF) transceiver and an antenna which emits an RF carrier interrogation signal to activate the tag and read tag data from it and, in some cases, to supply electrical power to the tag. The RFID reader may decode the tag data, or, more typically, sends the tag data to a host computer running RFID software/middleware for processing and decoding. The RFID reader may be a mobile reader, such as a handheld reader, or a stationary hands-free reader such as a reader fixedly located in a tunnel, a door portal or a toll booth.
The RFID tag typically comprises an RFID integrated circuit (IC) chip having a microprocessor, an RF transceiver circuit, and a non-volatile memory for storing the tag data, and an omnidirectional antenna, all mounted on a dielectric substrate. The RFID tag responds to the interrogation signal by modulating the interrogation signal in accordance with its tag data. The RFID tag may have an on-board battery, e.g., an active tag, or have no on-board battery at all, e.g., a passive tag, or have a small battery on-board, e.g., a battery-assisted passive tag. The passive tag uses the RF energy transmitted by the RF reader as its energy source. The RFID tag may be read-only, or read/write, once or multiple times.
Laser-based and solid state-based optical scanners are also well known in the field of automatic data capture. Such optical scanners have been used, in both handheld and/or hands-free modes of operation, to electro-optically read optical codes, such as one- and/or two-dimensional bar code symbols, each bearing elements, e.g., bars and spaces, of different widths and reflectivities, to be decoded. By way of example, a common one-dimensional symbol used in point-of-sale applications is the Universal Product Code (UPC) printed on a label that is attached to an object to be identified. The UPC-A code is a twelve-digit optical pattern of bars and spaces that format and encode a UPC digit string. Each digit is represented by a unique pattern of two bars and two spaces. The bars and spaces are of variable width, i.e., they may be 1, 2, 3, or 4 units (modules) wide. The total width for each digit is always 7 modules. To represent the twelve digits of the UPC-A code requires a total of 7×12=84 modules.
RFID technology provides certain advantages over optical scanner technology. Optical scanners optically transfer information from optically coded printed labels, whereas RFID readers use radio waves to transfer data from RFID tags. RFID tags have a greater memory capacity than UPC-A symbols. RFID technology allows for non-contact, wireless reading. The electromagnetic field generated by the tag antenna may be constant or periodic, or activated by an actuator such as a sensor or a trigger. Advantages to RFID technology include non-contact reading of multiple tags at the same time, at a far distance, e.g., several meters away, without the need for line-of-sight interrogation of each and every tag. The major advantage of optical scanner technology is its extremely low cost.
Although RFID tags can be used as a substitute for printed labels, it is sometimes desired to simultaneously employ both RFID and optical scanner technologies on the same object. While the RFID tag may be used to store and communicate a relatively larger amount of digital information, an additional machine-readable, or human-readable, optical code is also often desired to identify the label itself, or to provide data redundancy, or to provide an alternative method for reading label information, or to provide branding. In such cases, the RFID tag is often placed in, on, under, or adjacent, the optical label.
Thus, in accordance with the prior art, as depicted in FIG. 1, a UPC-A code 10 is printed with ink on a label 12 that is attached to an object 18, and is optically read by an optical scanner 14 that is connected to a host computer 16. An RFID tag 20 is affixed to the object 18, e.g., in, on, under, or adjacent, the label 12, and is read by RFID technology by an RF interrogator 22 that is connected to the host computer 16. Sometimes, a part, or all, of the RFID tag 20 is incorporated into the code 10. For example, the tag antenna can be configured to look like the UPC code. Even so, according to the prior art, an optical scanner 14 is always needed to read the code 10.
As advantageous as the known RFID interrogators 22 and optical scanners 14 have been in reading data from tags and labels, one concern relates to the additional requirement of associating or synchronizing the code data on the label with the tag data on the tag. As previously noted, the tag memory has to be programmed, or commissioned, with the encoded tag data, either during manufacture, or in the field either once or multiple times. In each case, the tag data has to be synchronized with the code data. This requires the optical scanner to be operated each time that the tag is commissioned. This consumes time and effort and may not always be performed. As a result, the tag data and the code data may be mismatched, and the RFID tags cannot readily be re-used.
Accordingly, there is a need to provide an arrangement for, and a method of, associating the tag data from the RFID tag with the code data from the optical code on the RFID tag, without requiring the necessity, time or effort for an optical scanner to be operated.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The tag, arrangement and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.